The identity of an ID candidate may conventionally be verified using a token, such as a card or badge, that is presented to an ID checker for verification. The token may carry a code, such as a barcode, that carries information about the ID candidate. The token may carry biometric data, such as a photograph of the ID candidate, so as to bind the token to the ID candidate. However, such conventional systems are prone to fraud, since the token may be stolen or counterfeited. They are also inflexible, in that the information they provide is static. Often, they are only designed for a single purpose.
Patent publication WO-A-2011/153355 (McKenzie) discloses a method of verifying permission to use a payment system, where the customer presents a communication device to a merchant, who extracts account information from the device, and sends a request for identification verification information to be sent to the device, or to an alternate display. The merchant can then compare the identification verification information to the customer to determine if the customer is authorised to use the account.
Patent publication US-A-2009/0106150 (eBay) discloses a system where an individual may prepare a token authorising a requesting party to obtain access to specified information associated with the individual.